Electrical connector



July 25, 1967 R. A. PATTON, JR 3,333,232

ELECTRICAL CONNECTOR Filed June 17, 1964 4 Sheets-Sheet 1 INVENTOR.

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July 25, 1957 R. A. PATTON, JR 3,333,232

ELECTRICAL CONNECTOR Filed June l'. 1964 4 Sheets-Sheet 2 INVENTOR l 24 /Pqg A/ptanyfr;

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July 25, 1967 R. A. PAT-row, JR

ELECTRICAL CNNBCTOR 4 Sheets-Sheet 3 'Filed June 1.7, 1964 July 25, 1967 R. A. PATTON, JR

ELECTRICAL CONNECTOR 4 Sheets-Sheet 4 Filed June 17, 1964 Pf w w Ry, o f m m m. am mvl m mm ma .Y r QSNQM QK W aw 0 eww 1 A. wv M.. M w y ,A 4u dmv 8^ n Smm mm ev s Y United States Patent O 3,333,232 ELECTRICAL CONNECTOR Roy A. Patton, Jr., 6030 North Shore Drive, Grabill, Ind. 46741 Filed June 17, 1964, Ser. No. 375,798 9 Claims. (Cl. 339-182) The present invention relates to an electrical connector, and more particularly to a multiple circuit connector composed of plug and socket parts which may be detachably connected together.

The development of miniaturized and microminiaturized electronic equipment has, as a matter of necessity, forced the development of miniaturized components such as capacitors, transistors, inductors, connectors and the like. As a result of this miniaturizing, redesign of these components has been required, and in some instances such redesigned, miniaturized components have suffered a considerable loss in reliability. Such components quite frequently constitute only a small part physically of equipment and systems of substantial size, but failure of the part can produce equipment and system failure. Problems have been encountered in the miniaturizing of connectors and to lit them into the space limitations permitted the electrical or electronic equipment with which the connector is associated. It has been found that such miniaturized connectors are a constant source of trouble and equipment failure.

It is therefore an object of this invention to provide an electrical connector and a method for fabricating the same having detachable parts which are extremely small in size yet are reliable, durable and eicient in use.

It is another object of this invention to provide an electrical connector wherein a maximum number of circuits can be reliably, operatively assembled into a minimum size unit.

It is yet another object of this invention to provide a multiple circuit connector having miniature and microminiature contact elements which are so constructed and arranged as to substantially minimize the chances of damage thereto because of mishandling or rough usage.

It is yet another object of this invention to provide in a miniaturized, detachable connector a unique contact arrangement which permits mating of multiple contacts with a minimum of contact resistance.

Other objects will become apparent as the description proceeds.

The above-mentioned and other features and objects of this invention and the manner of attaining them will become more apparent and the invention itself will be best understood by reference to the following description of an embodiment of the invention taken in conjunction with the accompanying drawings, wherein:

FIG. 1 is a side View of one embodiment of this invention;

FIGS. 2a and 2b are side views of the plug and socket parts of the connector of FIG. 1;

FIGS. 3a through 3cc are end and side views, respectively, of parts used in the fabrication of the connector of FIG. 1;

FIG. 4 is a contact-end view of the connector section of FIG. 2a;

FIG. 5 is a perspective view of the connector section of FIG. 2a;

FIG. 6 is an axial, sectional view of the connector of FIG. l;

3,333,232 Patented July 25, 1967 ICC FIG. 6a is an enlarged, fragmentary, sectional view of one of the contacts used in the connector part 0f FIG. 2a;

FIG. 7 is a fragmentary view, in part-axial section of the male and female portions of a slightly different embodiment of this invention;

FIG. 8 is a cross-section taken substantially along the section line 8 8 of FIG. 7;

FIG. 9 is a view similar to FIG. 7 but with the male and female parts connected together;

FIG. l0 is an enlarged fragmentary view of one male and one female contact element completely separated;

FIG. l1 is a View like FIG. l0 but with the contact elements partially engaged; and

FIG. 12 is a cross-section of another connector em- A bodiment.

Referring to the drawings, and more particularly to FIGS. 1 through 6a, an electrical connector indicated by the numeral 20 is composed of two parts, a male part or plug 22 and a female part or socket 24. These two parts are constructed almost identically such'that a description of one will substantially suffice for a description of the other. First, the construction of the plug 22 as shown specically in FIG. 2a will be considered.

In the main, the connector is composed essentially of a cylindrically shaped body of insulating material. This material is preferably plastic and may be in the form of Mylar, Teflon, polyethylene, vinyl, Bakelite, phenolics and the like. Whatever material may be used, the body should be relatively rigid and should not deform under localized pressure or deform as does soft rubber. When compared to the metallic contact elements which will be described later, the body material may be regarded as rigid and non-flexible.

The bodies of the plug and socket 22 and 24 are essentially composed of three Vplastic sleeves as shown in FIGS. 3a, 3b and 3c. Here again, the particular construction of the body of the plug 22 will be described. The three sleeves are essentially cylindrical in shape, the inner sleeve being shown in FIG. 3a, the intermediate sleeve in FIG. 3b, and the outer sleeve in FIG. 3c. The inner sleeve of FIG. 3a indicated generally by the numeral 26 as Well as the remaining sleeves are made of the plastic material previously described. The particular sleeve 26 is provided with a plurality (and in the illustrated case four) of axially extending grooves 28 which are equally circumferentially spaced apart. These grooves 28 preferably are identical, are of uniform depth and width throughout the extent thereof and in the illustrated embodiment are preferably rectangular.

The intermediate' sleeve of FIG. 3b indicated generally by the numeral 30 is of a diameter which will snugly telescope over the sleeve 26 and is provided in its outer peripheral surface with a plurality of axially extending grooves 32 which are of identical size and shape to the grooves 28. These grooves 32 are equally spaced circumferentially, and in the illustrated embodiment are eight in number. As shown in the comparative size FIG. Saa and FIG. 3bb, the sleeve 30 is substantially shorter than the sleeve 26. The reason for this will be explained more fully later on.

The third and outer sleeve shown in FIG. 3c and indicaed by the numeral 34 is of a size which will snugly telescope over the sleeve 30 and has a length shorter than the sleeve 30 as shown in the comparative size FIGS. 3bb and Sec.

In each of the grooves 28 of the inner sleeve 26 is securely fitted a straight, elongated, bar-like pin or Icontact element indicated by the numeral 36. This element 36 is rectangular in cross-section and of substantially the same size and shape as the groove 28. Also, this element 36 is of substantially the same length as the sleeve 26 as shown in FIG. Saa. A suitable adhesive material may be used for the purpose of securing the elements 36 in the respective grooves 28; however, the grooves 28 may be so sized 'as to receive the elements 36 in tight, gripping relation.

With all of the elements 36 assembled into the four grooves 28, the sleeve 30 is telescoped thereover to a position as shown in FIG. 6. The outer surfaces of the elements 36 are preferably curved so as to conform to the cylindrical periphery ofthe sleeve 26. With the sleeve 30 intimately and snugly telescoped over the assembly of the sleeve 26 and elements 36, the latter are further secured in position in passageways formed by the grooves 28 and the sleeve 30, thus the sleeve 30 provides a convenient means of forming the passageways and of securing the Velements 36 to the sleeve 26.

A series of contact elements as indicated by the numeral 38 in FIGS. 3b and 3bb of the same cross-sectional size and shape as the grooves 32 are fitted into respective ones of the latter in the same way as just described in connection with the sleeve 26. These elements 38 are of the same length as the sleeves 30 as shown in FIG. 3bb and when assembled into the grooves extend from one end to the other of the latter. Y

The outer sleeve 34 is snugly and tightly telescoped over the assembly of sleeve 30 and elements as shown more clearly in FIG. 6 thereby securing the elements 38 in position.

The sleeve 30 is positioned midway between the ends of the sleeve 26 as is the sleeve 34 on the sleeve 30, as shown more clearly in FIG. 6.

The elements 36 and 38 are of some suitable conductive metal, examples being brass, copper, aluminum, gold, silver, platinum or alloys thereof. A particularly useful material is beryllium copper. As will appear from the following description, it is desirable for these elements 36 and 38 to be resilient and in this respect to correspond to bar springs.

The Iconstruction thus far described is of stepped diam- Yeter configuration at the opposite ends as shown clearly in FIG. 2a. The right-hand end may be regarded as the contactor or plug end, while the opposite end may be considered as the terminal end. The plug ends of the sleeves 26 and 30 are of equal lengths; however, these lengths may vary depending upon design requirements.

At the terminal end, the innermost elements 36 are longer than the other elements 38 and extend axially therebeyond. This permits easy attachment, such as by soldering or Welding, of wires to the terminal ends of the elements 36. This is particularly important in the case in which the connector is extremely small in diameter. Similarly, the elements 38 project from the end of the sleeve 34 and are exposed for connection to additional wires. The attachment of wires to the terminal ends of the elements is illustrated diagrammatically in FIG. 1. Y

Y At the plug end (FIG. 2a) the ends or contacts of the elements 36 and 38 are embedded in the respective sleeves 28 and 30 but have the outer surfaces thereof fully exposed. These surfaces preferably are peripheral extensions of the respective sleeves so as to be ush therewith. In some cases, itis desirable that these element 36 surfaces be raised slightly above theperipheries of the respective sleeves 30 and 26 for reasons which will lbecome apparent from the following description.

The combination of the plug ends of the sleeves 26 and 30 and the elements 36 and 38, as plug units, are formed with detent shapes. In axial section, and considering the plug end only of the sleeve 28, the plug surface is smoothly undulating with the crest 40 being adjacent to the end and the valley 42 being rearwardly thereof. The plug end or contact 43 of the element 36 is identically formed indicated by the numerals 40a and 42a in FIG. 3aa. Y

The plug end of the sleeve 30 and its contact elements 38 are identically formed. l

As shown more clearly in FIG. 6a, immediately beneath the contact 43 of each element 36 and 38, the respective portions of the sleeves 26 and 30 are undercut or :formed to provide for a tapered space or gap 44. Thus, the contact portion 43 of each element 36, 38 may be deflected radially inwardly until Vthe bottom of the gap 44 is engaged. It is desirable for the contact 43 to be resilient such that when the deecting force is removed therefrom, it will spring back to the position shown in FIG. 6a.

The female part 24, shown in FIGS. .2b and 6, is fabricated essentially the same as the male part 22, with the exception that the three sleeves 46, 48 and 50 may be of the same length and are telescoped in staggered relation to provide the socket configuration indicated by the numeral 52. The sleeves 46, 48 and 50 with the respective contact elements 53 and`54 therein are of substantially the same diameters and cross-sectional shapes and dimensions as the sleeves 26, 30 and 34 and the elements 36 and 38. The contact elements 53 and 54 are the same in number as the elements 36 and 38 and are also spaced circum-v ferentially apart the same as the respective elements 36 Y and 38. The socket 52 is essentially divided into two portions, the one portion indicated by the numeral 56 in FIG. 2b being of the same Icomplementary size and shape as the plug end of the sleeve 30 so asto mate therewith, and the other, inner socket 58 being formed between the sleeves 48 and 46 and of the same complementary size and shape as the plug end of the sleeve 26 so as to mate intimately therewith.

The socket ends or contacts 60 of the contact elements 5,3 and 54, as shown more clearly in FIG. 6, are shaped to complement the detent configuration of the plug contacts 43 (40a, 42a) of the elements 36 and 38. Similarly, the socket 56 portion of the sleeve 50 is of complementary shape to the detent configuration ofthe plug end of the sleeve 30 so as to intimately t the same. y

As shown more clearly in FIG. 6, the inner peripheral surfaces of the socket contacts 60 of the contact elements 53 and 54 intimately axially overlie and lengage the outer peripheral surfaces of the plug contacts 43 of the elements 36 and 38. Desinably, the inner diameter of the socket contacts 60 is made Vslightly smaller than the companion portions of the outer diameter of the plug contacts 43 such that when the male and female parts 22, 24V are engaged, plug contacts 43 will be sprung radially inwardly slightly so as to provide intimate conductive contact with the socket contacts 60.

While the plug contacts 43 can be spring inwardly'because of the relief 44 formed in the respective sleeves-26, 30, still it is within the scope of this invention to relieve the contacts 43 of the elements 36, 38 -for permitting such springingaction. Also, as will now be obvious,it is not necessary to limit the contact movement to the male member 22 inasmuch as the socket contact 60.01'V the respective sleeve portions may be relieved to permit these parts to flex radially slightly. In arminiature or .microminiature Y version of the connector thus far described, the contact Y elements 36, 38, 52, 54 are extremely small and may correspond to size No. 34 copper wire. Obviously, if two ends of a wire of this size were butted together, the contact resistance would be extremely high as the area of contactV as is well known in the art, low 'contact resistancein a Y connector used' in miniaturized electronic equipment is au essential requirement in almost every equipment design.

The detent shapes of the plug and socket portions of the parts 22 and 24 are such as to permit the two parts to be connected and disconnected manually. The detent curvatures of the plug and socket portions may be gradual and elongated as already shown and described or in the alternative may be sharply pronounced and relatively short as will be explained later in connection with FIGS. l0 and 11. Obviously, modifying the detent shapes of the plug and socket portions of the connector will determine the ease -with which the parts may be connected fand disconnected. Also, the degree of rigidity of the assembly of the two parts when connected together will be determined by the detent configuration. The principal purpose of the detent is to lock the two parts 22 and 24 together and to resist separation thereof. While no means other than the detent has been shown for locking the male and female parts together, still conventional screw-type couplings may -be added to the outer sleeves 34 and 50 for this purpose if a tighter connection between the two parts is desired.

A slightly different embodiment of the invention is shown in FIGS. 7 through ll wherein the contact ends of the male and female parts are tapered. Like numerals with the suiiix a will indicate like parts in this alternative embodiment. Instead of using only two support sleeves, this alternative embodiment uses three such sleeves as indicated by the numerals 26a, 30a and 62. Additional contact elements 63 are fitted into the sleeve `62. This permits the use of a larger total number of contact elements and serves to demonstrate that .an extremely large number of elements can be packed into a relatively smal cylindrical space.

A centering pin is securely coaxially fitted to the interior of the sleeve 26a and projects therefrom as shown. A soft rubber ring 66 is shown attached to the outermost sleeve 30a for engagement -with a similar sleeve 68 on the socket member 24a whereby the connector when joined may be substantially hermetically sealed. The plug end of the male .part 22a is formed with a tapered configuration as shown, with the contact ends 43a projecting axially slightly beyond the adjacent tapered surfaces of the respective sleeves 26a, 30a and 62. These latter sleeves in the portions radially beneath the contact end 43a are relieved at 44a substantially the same as previously described such that the ends 43a can spring radially inwardly.

The female part 24a has sleeves and contact elements which are of identical size, shape and position as the companion parts of the plug 22a. The inner diameter 70 of the inner sleeve 46a, however, is made to such size as to have a slip-lit with the projecting portion of the centering pin 64. The pin 64 and the socket 70 may be pro vided with key and slot portions 72 and 74, respectively, as shown more clearly in FIG. 8 for the purpose of rotationally locating the male and female parts 22a, 24a with respect to each other. The relative positions of the contacts 43a and 60a of the male and female parts, when the latter are securely mated, are shown in FIG. 9. The detent portions axially overlap and engage and lock against axial withdrawal of the two parts. On the other hand, there is enough space provided for the contact ends A43a to ex such that the parts can be disconnected past the detents. The contacts 60a may be undercut also, if desired, to provide space 44h for the same to yflex radially. In the process of engaging the male and female contact ends 43a and 60a, reference may be made to FIGS. l0 and l1 wherein FIG. l() shows the two contacts 43a and 60a as approaching each other and FIG. 11 shows the crest portions of the detents as being engaged while the two elements 36a and 54a are being moved axially toward each other. As drawn, the contact 43a in FIG. 11 is shown slightly depressed, thereby indicating how the detent action operates to ex the contact 43a radially inwardly.

While the contacts 43, 60, 43a and 60a are shown as having detent portions, an alternative concept comprehends the contact portions as being lsubstantially at and extending parallel to the axis of the connector. The mating portions of the contacts 43 and `60 on the one hand and 43a and 60a on the other hand would have to be of such diameter in the connector assembly to axially overlap and engage thereby insuring substantial area contact between the contact elements so as to maintain contact resistance to a minimum, the extent of overlapping being of great importance with respect to wiping and locking action. Obviously, since the inner portion of the connector assembly as shown in FIG. 1 is hollow, a guide pin arrangement such as that described in connection with FIG. 7 can be used therein, or with guide pin removed, the connector assembly can be pressurized. The guide pin can be mounted securely in the opening lof the inner sleeve 26 so as to project from the plug end of the male part 22. The projecting end of this pin can t into the opening of the sleeve S2 of the female part 24. This particular arrangement is desirable in the arrangement of FIG. 1 where it is necessary that the same contacts mate every time the two parts 22 and 24 are brought together.

However, since the plug and socket coniiguration of the connector parts of FIG. 1 and FIGS. 2a and 2b are of stepped diameter, they serve the purpose of a coaxial locating pin. If it is desired in such an arrangement to always locate the contacts 43 and 60 in the same position each time the parts are connected and disconnected, two indexing marks 76 and 78 on the exterior of the male and female parts 22 and 24 may be used. Whenever these marks 76 and 78- are in alignment, al1 of the various contacts are brought into proper predetermined registry. Various other positive indexing mechanisms may be utilized such as the sleeve type provided with an external indexing mechanism. Y

Recapitulating the construction thus far described, if a male guide pin and keyway is used, it is surrounded by a sleeve of insulation material such as Mylar, Teon, polyethylene and the like. The outer periphery of the sleeve which is of a predetermined wall thickness is provided with a series of axially extending grooves. Each groove receives an elongated metallic conductor which is suitably secured in place. Another tube or sleeve of insulation of predetermined wall thickness is provided with a circumferential series of axially extending grooves which are also provided with elongated metallic conductors. This sleeve is telescoped snugly over the rst sleeve so .as to secure the conductors therof in position. This process of assembling sleeve and conductor assemblies may be repeated as many times as may be desired in order to obtain as many conductors or connectors 'as desired. As the circumference of each and every additional sleeve becomes greater, so does the number of conductors or connectors contained therein. Utilizing this cylindrical or circular concept permits maximum utilization of a minimum of material. Also, since the basic configuration is circular or cylindrical, a minimum of -actual space is required for obtaining a given number of conductors or contacts.

Since the actual larea of contact of each individual conductor, as shown in the drawings, is arcuate, it is apparent that a much greater area of actual contact between mated male and female connectors prevails over other known connector concepts. Because of the unique method of insuring intimate engagement between male and female contacts, even though a connector assembly may contain a relatively large number of conductors, proper electrical connection between the respective male and female contacts is always assured.

Of extreme value in this direction is the fact that the contacts 43, 60, 43a, 60a are protected on the bottoms and sides thereof by the sleeve material. If a connector part should be dropped, the chances are quite remote that the contacts will be bent. Since such contacts in miniature connectors are extremely small, corresponding to No. 34 gauge wire or gauges even smaller than this, it is obvious that a slight bump or touching with another object can bend a contact. However, in the design of this invention,

vrotary switch.

the contact is protected on three sides such that rough handling or bumping of the contacts can be Y tolerated without any material danger of producing any damage. Thus, the male and female parts of a connector assembly can be reliably connected and disconnected many times with full and complete assurance that all of the conductors will properly mate.

Statistics within the connector industry support the fact that a considerable percentage of existing problems associated with connectors and terminations are a result of damaged connector pins and sleeves which this concept, as disclosed, avoids.

Also, of great significance is the fact that as additional circles of connector pins are added, the ability of the units to withstand greater shock and vibration is enhanced rather than decreased as is the case with pin and sleeve concepts.

With respect to the terminal ends of the male and female parts 22 and 24, by means of the coaxial arrangement of all of the various conductors, the greater number of .conductors in the outer regions of the assembly serve to provide additional strength to the inner regions against bending, fracture or breakage due to the overlapping, on a longitudinal axis, of each circle of terminals as outward progression occurs. Each additional circle of conductors increases the connector strength, since a greater number of conductors is used in the outermost circle. Thus, even in miniature sized units, the coaxial, overlapping arrangement conducts to an extremely strong, relatively speaking, structure which will stand the usual stress and strain involved in use of miniature electronic equipment due to the dispersed area of stress afforded lead wires when attached to the terminals. Y

Referring to the embodiment of FIGS. 1 through 6, by spacing all of the conductors 36 and 38 in both the male and female parts 22 and 24, equally apart, it is possible to use the assembly as a rotary switch for connecting different circuits. As shown in FIG. 1, with the two marks 76 and 78 registered, the conductors of the respective male and female parts 22, 24 are connected into a first set of circuits. By merely rotating the female part 24 relative to the male part 22a distance corresponding to the angular spacing between conductors 36, 38, different conductors can be brought into contact thereby changing the circuit connections. Thus, the connector assembly 20 doubles in purpose as not only a connector but also a This switching action when associated with computers, test equipment and the like is of great importance in that one pair of connectors having, as an example, forty-eight (48) properly spaced pins is capable of eifecting five hundred eighteen (518) various circuitry variations. This switching capability lis thereby capable of reducing previously utilized cable and connector assemblies by ratio as great as ninety-to-one (90-to-l), approximately.

This switching action may be accomplished by discon- -necting male and female units, presetting the guide pin or sleeve assembly to a desired position prior to mating of the units thereby providing a foolproof positive circuitry combination or by rotating the female unit either clockwise or counterclockwise within the male unit (which direction is predetermined).

In one embodiment of this invention, the conductors 36 and 38 are positioned in radial alignment such that a given angle of relative rotation between the two parts 22 and 24 will always result in the respective contacts being Vbrought into proper registry.

VWhile the bodies of the connector parts have been disclosed as being truly cylindrical, polygonal shapes are distinctly possible and are to be considered as being included within' the generic concept of this invention so ylong as the appended claims are not violated.

tional shape without departing from the scope of this invention as defined by the claims. 7 K

In FIG. 12 is illustrated a further embodiment of this invention. Thisriigure is a cross-section of a unit almost identical to that shown in FIGS. 4, 5 and 6. The primary difference between this embodiment of FIG. 12 and the arrangement of FIGS. 4, 5 and 6 is that an additional set of contacts has been coaxially tted around the outer set 38 and the external sleeve has been assembled over this latter set of contacts. Referring to FIG. 12, like numerals indicate like parts. The sleeve 34a is the same as sleeve 34 of FIG. 4 with the exception that the outer periphery thereof is provided with a circular series of axially extending grooves 76 which are radially aligned with the contactor elements 43, 38 as shown. These grooves 76 `are much smaller than the grooves in the inner'Y sleeves and receive correspondingly smaller, elongated contactor elements 78. Other than the fact that these elements 78 are smaller in cross-section than the elements 38, they areV to as enable pins, are in radial alignment with the righthand side or edge of the contactor elements 38. It will also be obvious from close examination that the crosssectional area of these pins 78 is about one-tenth (1/10) that of the area of the elements 38. The reason for this positional and size relationship may better be explained by considering a typical external circuit connection with which this connector embodiment of FIG. 12 may be used. One of the pins 78, in such a circuit, is connected toa relay coil 80 at one end of the latter while the other endY of the latter is connected to a similar pin 78 (not shown) on a female unit. A battery 82 is series-connected with the .coil 80. When the male part of FIG. 12 and the Vfemale part are connected together in proper alignment so that theV pins 78 contact each other, the relay80 is energized thereby closing the contacts 84. These contacts 84 are wired to the radially adjacent contacts 38a such that a circuit connected to this contact 38a will haveelectrical power applied thereto. In other words, until theV male and female contact elements 78 are engaged, no

power will be applied to the circuit which includes theY contact element 38a. For the purposes of this example, it is assumed that the power connected to the contacts 38a is considerable suchthat as the male and female contacts 38a are brought into contact with each other, considerable arcing or sparking could occur. By means of this circuit arrangement just described, this highV power Y will not be applied to the circuit of the contacts 38a until after the contacts 78 have been brought into engagement.

In using this enable concept of FIG. 12, the male and female parts are initially fitted together such that none of the contacts will be in engagement with each other. The two parts are then rotated such that the male and female contacts 38a will first engage and be ninetenths (%0) fully engaged before the enable contacts 78 come into engagement. The moment these latter contacts come into engagement, the relay 80 will be energized, the contacts 84 will be closed and power will be applied to the circuit of the contacts 38a. It is thus seen that by means of this rotary, enablef pin arrangement, power is not present in the contacts 38a until they are almost fully engaged, thereby preventing arcing and sparking.

Since the design of the present invention permits the use of a multiplicity of connectors in a signicantly small, cylindrical package, it is possible to maint-ain outside drimensions in the connector assembly which are consistent with the outside dimensions of cable and harness with which the connectors may be used. This minimizes the problems of weight, space, sealing, pressurizing and the like to which a considerable amount of significance must be attached. Also, the concept of this invention affords a quick disconnect capability which again is extremely desirable and important in most applications such as electronic Wiring harnesses which are used to connect different pieces of electronic equipment together.

Since now the outside dimensions of connectors and cables or harness assemblies to which they are being mated may be maintained, it is not only possible but extremely desirable to prefabricate and test cables and/or harness 4assemblies with connections aixed as sectionalized assemblies. Said assemblies now having consistent outside dimensions permit pulling through sleeves, conduit, bulkheads, etc., thus facilitating significant cost reductions With respect to assembly of equipments on wiring of buildings, etc. Also, savings lof great significance in the fields of reli-ability and maintainability are thus afforded with respect to time, materials, manpower and costs.

While there have been described above the principles of this invention in connection with specific apparatus, it is to be clearly understood that this description is made only by Way of example and not as a limitation to the scope of the invention.

What is claimed is:

1. An electrical connector comprising a substantially rigid cylindrical body of insulating material, a plurality of axially extending elongated contact elements embraced within said body, said elements being larranged into a iirst circular set and being circumferentially spaced apart, said body at one end having a rst reduced diameter cylindrical end portion, said elements extending axially along said end portion adjacent to the surface thereof, those portions of said elements which extend along said end portion having exposed surfaces which constitute contact surfaces, that portion of said elements which carries said contact surfaces being resilient and elongated in a direction parallel to the axis of said body, the surface of said end portion having elongated recesses substantially parallel to the body axis which receive in protective guiding relation said contact-surface portions of said elements, respectively, there being one contact-surface portion Within a single recess, said recesses each including a bottom radially spaced from the respective contact-surface portion for permitting the latter to ex radially with respect to said body, said contact surfaces being disposed substantially ush with, but having at least in part projecting slightly radially beyond the surface of said end portion such that all said contact surfaces and the surface of said end portion conjointly provide a geometric shape corresponding to a generally cyclindrical surface, each contact surface being undulated longitudinally with a detent crest being located distally from a detent valley, said part including said detent crest, said detent crest as well as said valley being fully radially exposed in the surface of said end portion, thereby being fully backed by said end portion and also completely accessible radially without interference from the remainder of said body.

2. The connector of claim 1 in which said crests and valleys are curved and smoothly merge one with the other.

3. The connector of claim 2 in which said end portion extends beyond said one end of said body thereby providing a male contactor section.

4. The connector of claim 2 in which said end portion is recessed Within said one end of said body thereby providing a female contactor section.

5. The connector of claim 2 in which said body has a plurality of axially extending passageways within which said elements are secured, said passageways extending parallel to the body axis, said elements being arranged in a cylindrical pattern, and said recesses being extensions of said passageways, respectively.

6. The connector of claim 2 including a second circular set of said contact elements coaxially surrounding said first circular set, said body having a second reduced diameter cylindrical end portion of larger diameter than and extending beyond one end of said first end portion, said second elements extending axially along said second end portion adjacent to the surface thereof, those portions of said second elements which extend along said second end .portion having exposed surfaces which constitute second contact surfaces, said second contact surfaces and that portion of said second element which carries said second contact surfaces being resilient and elongated in a direction parallel to the axis of said body, the surface of 'said second end portion having elongated recesses therein substantially parallel to the body axis which receive in protective guiding relation said second contactsurface portions of said second elements, respectively, there being one second contact-surface portion within a single second recess, said second recesses each including a bottom radially spaced from the respective contactsurface portion for permitting the latter to ex radially with respect to said body, said second contact surfaces being disposed substantially ush with, and at least in part projecting slightly beyond, the surface of said end portion such that all said second contact surfaces and the surface of said second end portion conjointly provide a geometric shape corresponding to a cylindrical surface, each second contact surface being undulated longitudinally with a detent crest being located distally from a detent valley, said detent crest slightly extending radially beyond its recess and the surface of said second end portion, said second detent crest and valley being fully radially exposed in the surface of said second end lportion, thereby being fully backed by said end portion and also completely accessible radially Without interference from the remainder of said body, said second crests and valleys, respectively, being curved and smoothly merging one with the other.

7. The `connector of claim 3 including a second cylindrical body of insulating material, a plurality of axially extending elongated second .contact elements embraced Within said second body, said second elements being arranged into a second circular set and being circumferentially spaced apart, said second body at one end having a second reduced diameter cylindrical end portion of substantially the same diameter as said first end portion, said second elements extending axially -along said second end portion adjacent to the surface thereof, those portions of said second elements which extend along said second end portion having exposed surfaces which constitute second contact surfaces, said second contact surfaces and that portion of said second elements which carries said second contact surfaces being resilient and elongated in a direction parallel to the axis of said second body, the surface of said second end portion having elongated recesses substantially parallel to the second body axis which receive in protective guiding relation said second contactsurface portions of said second elements, respectively, there being one second contact-surface portion Within a single recess, said second recesses each including a bottom radially spaced from the respective second contactsurface portion for permitting the latter to ex radially with respect to said second body, said second contact surfaces being disposed substantially flush with the surface of said second end portion such that all said second contact-surfaces and the surface of said second end portion conjointly provide a geometric shape corresponding to a cylindrical surface, each second contact surface being undulated longitudinally with a detent crest being located distally from a detent valley, said second detent crest and valley being fully radially exposed in the surface of said second end portion, thereby being fully backed by said second end portion and also completely accessible radially without interference from the remainder of said `rsecond body, said second end portion being recessed Within said one end of said second body, thereby providing av female contactor section; s-aid male contactor section telescopically fitting into said female contactor section, the end portion of the male contactor section slidably engaging the second end portion, the second contact surfaces slidably engaging, respectively, the first contact surfaces with the undulations -of both rst and second contact surfaces mating With each other, the undulations of one of the engaged contact surfaces being shaped complementary with the undulations of the other contacting surface, the contact-surface portions being preformed so as to force yieldably the engaged contact surfaces into engagement with each other.

8. The connector assembly of claim 7 wherein the rst and second elements of engaged contact surfaces are generally straight extensions of each other parallel to the body axes thereby corresponding to a straight conductor extending through the vassembled bodies.

9. The connector assembly of claim 8 in which lche engaged contact-surface portions are .in effect solidextensions of the respective contact elements.

References Cited UNITED STATES PATENTS 2,749,526 6/ 1956 Petersen 339,-61

2,892,990 6/ 1959 Werndl 339--182 X 3,001,167 9/=1961 Chesnutt et al; l339-89 3,235,832 2/1966 'Buchanan et al. 339--176 X FOREIGN PATENTS 1,078,627 5/ 1954 France. 408,748 6/ 1943 Italy. 1,083,359 1/ 1925 Switzerland.

,MARVIN A.V CHAMPION, Primary Examiner.

W. DONALD MILLER, Examiner.

2O I. R. MOSES, Assistant Examiner. 

1. AN ELECTRICAL CONNECTOR COMPRISING A SUBSTANTIALLY RIGID CYLINDRICAL BODY OF INSULATING MATERIAL, A PLURALITY OF AXIALLY EXTENDING ELONGATED CONTACT ELEMENTS EMBRACED WITHIN SAID BODY, SAID ELEMENTS BEING ARRANGED INTO A FIRST CIRCULAR SET AND BEING CIRCUMFERENTIALLY SPACED APART, SAID BODY AT ONE END HAVING A FIRST REDUCED DIAMETER CYLINDRICAL END PORTION, SAID ELEMENTS EXTENDIG AXIALLY ALONG SAID END PORTION ADJACENT TO THE SURFACE THEREOF, THOSE PORTIONS OF SAID ELEMENTS WHICH EXTEND ALONG SAID END PORTION HAVING EXPOSED SURFACES WHICH CONSTITUTE CONTACT SURFACES, THAT PORTION OF SAID ELEMENTS WHICH CARRIES SAID CONTACT SURFACES BEING RESILIENT AND ELONGATED IN A DIRECTION PARALLEL TO THE AXIS OF SAID BODY, THE SURFACE OF SAID END PORTION HAVING ELONGATED RECESSES SUBSTANTIALLY PARALLEL TO THE BODY AXIS WHICH RECEIVE IN PROTECTIVE GUIDING RELATION SAID CONTACT-SURFACE PORTIONS OF SAIE ELEMENTS, RESPECTIVELY, THERE BEING ONE CONTACT-SURFACE PORTION WITHIN A SINGLE RECESS, SAID RECESSES EACH INCLUDING A BOTTOM 